Cable-anchoring and sealing device



F b 2 1957 R. R. BROWN ETAL 2,783,298

CABLE-ANCHORING AND SEALING DEVICE Filed July 51, 1950 42 2 as H I .O.-it! H l INVENTORS.

. R. R. BROWN 8 C. L. BROWNLOW 170.3. I Y u A ORN 5 CABLE-ANCHORING ANDSEALING DEVICE Raymond R. Brown and Cecil L. Brownlow, Bartlesville,

Okla, assignors to Phillips Petroleum Company, a corporation of DelawareApplication July 31, 1950, Serial No. 176,806

3 Claims. (Cl. 174-59) This invention relates to seismometers. In onespecific aspect it relates to a seismometer case cover embodying acable-anchoring and sealing unit of novel design.

Heretofore, considerable difficulty has been experienced in providingelectrical connections to seismometer units. Seismometers are delicateinstruments which, when used in the field, are mounted in heavy metalcases to withstand considerable abuse and rough handling. The case mustbe so constructed so as to permit planting of the seismometer in theearth which is ordinarily accomplished by securing a thrust transmittingcoupling to the seismometer cover, this coupling receiving a rod bywhich the seismometer case is pushed a short distance into .the earth orlowered into a shallow drill hole and anchored at the bottom of thehole. To facilitate this planting, an elongated rod or a conical nose isdetachably secured to the lower end of the cover to facilitate insertionof the case into the earth. After the seismometer has been planted, thecoupling and rod are removed and the seismometer is used to measurereflected or refracted waves incident thereupon. The seismometer coveris' also provided with a fastening device to retain a chain or rope bywhich the seismometer can be removed from its planted position after theseismic exploration operation is completed. This device ordinarily takesthe form of a clevis which fits into two diametrically opposite openingsforming opposite ends of a single hole in the cover, the clevis, inturn, being secured to a rope or chain which extends above the surfaceof the ground. i

In addition to the aforementioned requirements, an electrical cableincorporating the electrical conductors for the seismometer must passthrough the cover and there must be a sealed joint at the pointonentrance of the cable to prevent moisture or water from entering thecover and injuring the delicate parts of the seismometer. Thecable-anchoring device must be of rugged construction to withstand abuseand rough handling of field personnel, it must not interfere with theplanting or lifting appliances, and it must not protrude beyond thesides of the seismometer case so as to prevent twisting or damagethereto through contactof the cable with the sides of the hole in whichthe seismometer is planted.

It is an object of this invention to provide a seismometer case andcover which adequately fulfills the aforementioned exactingrequirements.

It is a still further object to provide a cable-anchoring device whichis of rugged construction'and does not interfere with the planting orraising of the seismometer.

It is'a still further object to provide a cable-anchoring device sooriented that the cable does not extend beyond the sides of theseismometer case and in which the cable itself is, although ordinarilysecurely anchored, readily detachable for replacement or repair.

Various other objects, advantages and features of the invention willbecome apparent from the following detailed description taken inconjunction with the accompanying drawings, in which: I

Figure l'is a vertical sectional view of a seismometer incorporating thenovel cable-anchoring and securing device;

Figure 2 is a front elevational view, on a reduced scale, of thecover-case unit of Figure 1 with the planting coupling and rod in place;and

Figure 3 is a vertical sectional view of a modified cable-anchoring andsealing device.

Referring now to-Figure 1, a generally cylindrical metal casing 10 has afrusto-conical nose 11 formed integrally with the lower end thereof toform a casing or housing for a seismometer 12 mounted therein, aclamping ring 13 secured to an interior threaded portion 14 of thecasing forcing the seismometer into rigid engagement with the casing,the ring being held in position by a set screw 15. A detachable conicalnose 15a is secured to the lower end of portion 11 to facilitateplanting of the seismometer.

A metal cover 16 is secured to the casing 10 as by screw threads 17 andan annular gasket 18 of resilient material is provided to seal thejoints between the case and cover. The cover includes an enlarged lowersection 26 merging into a frusto-conical section 21 defining a slantingsurface 22 which is inclined with respect to the axis of the cover. Thefrusto-conical section 21, in turn, merges into an upper section 23 ofreduced diameter as compared with that of the lower section 20. Forpurposes of planting the seismometer, a coupling 25 can be seated upon athreaded connection 25a, this coupling being provided with a threadedplug 26 for receiving a planting rod 27.

It will be evident that the conical portion 11, 15a can be pushed ashort distance into the ground or anchored at the bottom of ashallowauger hole or other drill hole by pressure applied through therod 27. Once the seismometer has been planted in this manner, the rod 27and coupling 25 can be removed simply by lifting them clear of theseismometer cover.

In order to permit removal of the seismometer from a hole after aseismic exploration operation has been com pleted, the cover is providedwith a pair of diametrically opposite openings forming a part of a hole31 which openings receive a clevis 32, the clevis, in turn, having achain 32a secured thereto to enable the seismometer to be readily liftedfrom its planted position. In Figure 2, the nose 15a is replaced by along rod 15b having a blunt nose 15c to enable the nose to be pushedinto the mud and firmly anchored therein.

In accordance with the invention, a cable 33' incorporating two or moreelectrical leads 34 extends through the cover and is secured thereto bya novel cable-anchoring and sealing device 35. This device is receivedwithin .an opening 36 in the coventhe axis of the opening beingperpendicular to the inclined surface 22 and consisting of an innerportion 37 of reduced diameter, and an enlarged threaded outer portion38 which define an interior shoulder 39. The cable 33 has, adjacent itsend, an enlarged annular portion 40 of resilient material which isseated upon the shoulder 39. The terminal part of the cable extendsthrough the reduced portion 37 of the passage to the seismometer unit12.

An annular washer 41 is seated upon the enlarged cable portion 40, thecable and washer being rounded in a, complementary manner so that theseparts are disposed in interfitting relationship. A threaded clamping nut42 encircles the cable 33 and this nut, when tightened in the threadedouter portion 38 of passage 36, bears against the washer 41 and forcesthe enlarged portion 40 of the cable into sealing engagement with theshoulder 39, thus securely anchoring the cable inrposition upon thecover and preventing entrance of moisture or water through the opening36 to the delicate parts of the seismometer.

It is a feature of the invention that the cable-anchoring and sealingdevice 35 is positioned upon the inclined surface 22. As a result, thecable enters the cover at a position spaced inwardly from the walls ofcasing so that it does not scrape against the sides of the planting holeas the seismometer unit is lowered into the earth. Moreover, thepositioning of the anchoring device prevents the cable from interferingwith the coupling 25 and planting rod 27 together with the chain 32a andits associated fastening device.

In Figure 1, the anchoring device may be released simply by unscrewingnut 42, but, in order to replace the cable, it is necessary todisconnect leads 34 from the seismometer 12, which, of course, involvesremoval of the cap and lock ring 13. In Figure 3, I have disclosed astructure wherein the cable may be readily removed without unsolderingthe conductors or removing the seismometer cover, parts similar to thosealready described being indicated by like reference numerals in thismodification.

Referring now to Figure 3, a cable 33a incorporating conductors 34aterminates in a enlarged portion 40a of resilient material which isprovided with a plurality of sockets 44, one for each conductor 34a. Thewasher 41 and nut 42 are adapted to apply pressure to the enlargedportion 40a in the same manner as described in connection with Figure 1.An integral enlarged portion 46 of a cable 46a is seated against theshoulder 39 and provided with a plurality of plugs 47, one such plugfitting into each of the sockets 44. This portion 46 can be consideredto be a part of shoulder 39. The plugs, in turn, are connected toconducors 48, respectively, which lead to the seismometer unit 12 in thesame manner as the condoctors 34 of Figure 1.

It will be evident that tightening of the nut 42 transmits pressurethrough washer '41'to force the enlarged resilient portion 40a intosealing engagement with the enlarged portion 46 which, in turn, isforced into sealing engagement with the shoulder. This produces apositive anchoring and sealing of the cable as in the structure ofFigure 1. When the nut 42 is loosened, it will be evident that thesockets 44 may be readily detached from the plugs 47 with the resultthat the cable can be completely removed and disconnected withoutremoving the cover 16 and without unsoldering the leads 48 connected tothe seismorneter unit 12. This feature is valuable in practical fieldwork, since the cables oftentimes are broken or damaged outside theseismometer case. When the cable is so removed, cap 42 and washer 41 canbe reinserted and forced into engagement with cable portion 46, thussealing the interior of the casing.

While the invention has been described in connection with present,preferred embodiments thereof, it is to be understood that thisdescription is illustrative only and is not intended to limit theinvention, the scope of which is defined by the appended claims.

We claim:

1. In combination, a metal cover, an elongated housing threaded to saidcover to define a pressure-tight vessel, said cover having a flatcentral portion generally perpendicular to the axis of said elongatedhousing, and a surface inclined tosaid axis connecting said centralportion to the periphery of the cover, said inclined surface having abore formed therein extending through said cover with its axis generallyperpendicular to said inclined surface, said bore having a relativelysmall interior portion and a relatively large threaded outer portion,thereby to define an internal shoulder, a cable extending into saidopening, said cable having an integral enlarged portion of resilientmaterial positioned within the outer portion of said bore with one endof said enlarged portion engaging said shoulder, a washer encirclingsaid cable and engaging the other end of said enlarged portion, anannular threaded nut encircling said cable and bearing against saidwasher, said nut fitting within the threaded outer portion of saidpassage, whereby tightening of said nut forces said resilient enlargedportion of the cable into sealing engagement with said shoulder, andconnecting means on. the flat central portion of said cover, said cable,by virtue of said inclined surface, being confined within an extensionof the outer surface of said vessel, thereby to prevent damage to thecable as the vessel is raised and lowered in a bore hole.

2. The structure of claim 1 wherein said enlarged portion directlyengages said shoulder, and cable incorporates a pair of integralconductors extending from the interior of the vessel to the exteriorthereof.

3. The structure of claim 1 wherein a second cable extends from theinterior of said vessel to said shoulder, said second cable having anenlarged portion engaging said shoulder and the enlarged portion of saidfirst-mentioned cable bearing against said enlarged portion engagingsaid shoulder, and said first cable having sockets fitting into plugsextending from said second cable.

References Cited in the file of this patent UNITED STATES PATENTS1,200,368 Klug Oct. 3, 1916 1,858,816 Burkhardt May 17, 1932 1,974,422Hayes Sept. 25, 1934 2,275,762 Horton Mar. 10, 1942 2,449,085 PetersonSept. 14, 1948 2,477,172 Brownlow July 26, 1949 2,568,680 Frowe Sept.18, 1951 2,568,851 Flnde Sept. 25, 1951 FOREIGN PATENTS 632,798 GermanyJune 28, 1934 494,510 Great Britain Oct. 24, 1938

